Darier Disease - A Clinical Illustration of Its High Variable Expressivity.

Darier disease (DD), also known as dyskeratosis follicularis, is a rare genodermatosis classically characterized by persistent hyperkeratotic papules and plaques affecting the seborrheic areas. Due to its variable expressivity, it can present with very discrete clinical features for many years, leading to diagnostic errors and incorrect treatments. We report an unusual case of Darier disease in a 69-year-old male patient in which the classical features of DD had a remarkably late onset. This patient had a several decades' history of small, recurrent, scattered papules, limited to the face, for which he had received multiple diagnostic interpretations, such as acne or recurrent staphylococcal skin infection. We established the diagnosis of DD with superinfected lesions, and initiated treatment with intravenous antibiotics and oral retinoids. Results were extremely satisfactory in a very short time. This case shows an extremely unusual clinical course of Darier disease and is illustrative for the variable expressivity of the disease. It highlights the need to take dyskeratosis follicularis into account in patients with a longstanding history of persistent, hyperkeratotic papules, from unknown origin, even in the absence of the classical clinical findings.